Electronic Mailbox

The following have been selected from the questions received on the ASGAP World Wide web site over the past few months. You're welcome to comment on any issue concerning Australian native plants....growing, propagating or appreciating (even loathing!) ... anything.

If necessary, bung a message in a bottle if your net connection goes down!!

....and, if you'd like to contact any of the correspondents and no email address is listed, please feel free to do so through the editor.

Plants for Tasmania

In the middle of yet another drought with a garden of dead bushes, plants, grass, which I now call my desert, I am resolving to plant only native plants, which will not appeal to possums, rabbits and the odd wallaby!

Can you help me with a few suggestions? The soil is sandy, and I constantly add manure and straw. Do natives require manure?

I am on tank water and most of the past years the farm creek is dry except for a water hole which I can pump water from.

Isabell Hughes
Campania, Tasmania

It's difficult to make specific recommendations particularly as I'm based in Sydney and I only have a rough idea of your growing conditions.

The web site of the Tasmanian Region of the Australian Plants Society contains a fair bit of information on Tasmanian species so it would be worth checking out.

Regarding manure. The answer is "some do and some don't!!" The issue here is that "natives" is a very broad term and includes lots of different plants from lots of different plant families. As a general rule (and there will be exceptions), plants in the protea family may respond badly to manures, particularly if fresh and particularly if they contain much phosphorus. This group includes Banksia, Grevillea, Hakea, Isopogon. Plants in the myrtle family (Callistemon, Melaleuca, Leptospermum, Eucalyptus, etc) are generally more adaptable when it comes to fertilizing.

Probably your best bet would be to visit some specialist native plant nurseries in your area - they are in the best position to advise on suitable species for local conditions. There are some listed on the ASGAP website.

Tree Fern for Florida

I purchased an Australian Tree Fern in Florida and planted it in Zone 7 in Peachtree City, Georgia, south west of Atlanta.

There was no label on the fern other than to say that is was an Australian Tree Fern. I am wondering if it will survive in this climate.

Nora Dalen
Florida USA

The US climate zoning system doesn't have any meaning in Australia but I understand that Zone 7 means a minimum winter temperature of between -17 and -10o C (0 - 10o F).

There are a number of different species in the "Tree Ferns" group so, without knowing which species you have it's difficult to be specific. However, the most commonly available species (at least in Australia) are Dicksonia antarctica and Cyathea australis. Assuming you have one of these, they are hardy in tropical to temperate areas in a wide range of soils and, of course, they like plenty of moisture. They are tolerant of moderate to heavy frost but would rarely experience temperatures quite as low as Zone 7 indicates.

I'd put it in a protected position and hope for the best!

Photo of Cyathea australis - Fred Johnston (53k)

Propagation Problems

I am attempting to propagate various natives - Grevillea, Callistemon, and some exotics - viburnum, daphne, azalea. I have followed the technique described on your site, i.e put the pot of cuttings in to a clear plastic bag and tie the bag up, ensuring that the bag doesn't contact the cuttings by creating a frame. In the bag I have put a handful of wet sphagnum moss. Within hours there is plenty of condensation. I have left them in this state for 3 weeks.

On checking them I have found quite a bit of 'white mould' and subsequent death of cutting. I have kept the containers out of direct sun.

My questions are:

Should I not have them in plastic bags at this time of year (summer)?

Am I doing something wrong ?

Andrew Hannah
Australia

Good to hear that someone is making use of the propagation pages!

Re your questions....

Yes, you need the plastic covering. Summer heat would kill many of the cuttings.

No, you don't seem to be doing anything wrong.

Perhaps I should elaborate a little. The guidelines on the web pages are just general principles. Some species may need more elaborate methods (such as bottom heating and special hormones) and some may strike out in the open with little or no protection. Some species are also difficult to strike, no matter what you do.

The other problem is that what works for some people may not work for others due to differences in local conditions or differences in interpreting what is written in the guidelines. Most people tend to develop their own variations on propagating methods with experience. It is not unusual for first attempts to be a little less successful that people might hope for. However, persistence, and trying a few variations to the methods might help.

Here a a few suggestions and points to consider.

If rotting is occurring, try opening the plastic bag at night time to allow fresh air circulation. Don't forget to replace the covering in the morning.

Remove any diseased cuttings as soon as you see them.

Try spraying with a fungicide occasionally.

Try soaking the cuttings in a bleach solution before setting them. I use an 8 parts water to 1 part household bleach solution, soak the cuttings for 30 seconds and then rinse off well in clean water. Make sure you wear rubber gloves if you do this - the bleach solution is still very strong.

Don't mix different types of cuttings in the same pot.

I hope this helps but the best advice I can give is to persist and to try a few variations of your own - you will eventually work out methods that work for you.

Australian Medicinal Plants

I am doing a school project on Aborigines and would like some information on bush medicines. I would like to know what plants they used and for what problems.

If you could help me, I would be very thankful.

Tim Bendle
Australia

There's not a lot of information on aboriginal medicinal plants on the web but the following sites should provide some guidance. They mainly deal with bush foods but you will find some info on medicines.

If you have time, the book "Bush Medicine" by Tim Low would be worth checking at a library.

Best of luck with your project.

A Great Banksia!

I was hoping that you could help me. On a trip to Sydney last January I photographed a fascinating plant that I have recently identified as Banksia robur. I am planning to hang the photograph in my office and I was interested to know if there is a common name for this plant. Any assistance in this matter would be greatly appreciated. We have nothing like it growing here.

Kim Collins
British Columbia, Canada

....wonderful plant, Banksia robur.

Its common name is "swamp banksia". You'll find some more information on it on our main web site.

Photo of Banksia robur - Keith Townsend (43k)

Planting for Commerce

I have 2.5 hectares of vacant land in West Pinjarra (1.5 hrs South West of Perth, Western Australia). It is cleared except a few large gum trees. I wanted to grow some wildflowers that I could then sell commercially to makets, florists, etc. Preferably they wouldn't require a great deal of watering or attention as I live in Sydney at present but could ask someone to go there once a week if needed.

What do you suggest I could grow and ...

Is there a market in Perth?

How much water do they need?

What is involved in the planting to harvesting cycle and what time frame?

Any other relevant considerations?

Thanks a lot.

Steven Ellis
Sydney

Unfortunately the Society doesn't have the expertise to advise on commercial growing of wildflowers. This is an area where you need professional advice.

Apart from that, the Western Australian Agriculture Department should be able to offer advice ((if you try a search on"wildflowers" on their home page, you will find quite a bit of info on growing wildflowers commercially including items on starting out).

Hope that helps.

What's a Corymbia?

Recently a colleague and I were looking for Eucalyptus maculata on a 'tube list', and noted the name change to Corymbia maculata. Is this right? Why and when was it changed?

Just out of interest.

Theresa Whitten
Australia

Whether it's right depends on who you talk to!

It stems from a revision of the Bloodwood group of eucalypts that was published by Ken Hill and the late Lawrie Johnson in 1995 (in Telopea, the journal of the Royal Botanic Gardens Sydney). The effect of the revision was to raise the sub-genus Corymbia to genus level and thus transfer about 80 former Eucalyptus species to the genus Corymbia. A number of new species were also included in Corymbia at the same time.

Apart from C.maculata (spotted gum), other well known species transferred included Corymbia citriodora (lemon-scented gum) and Corymbia ficifolia (West Australian Red-flowering gum).

Needless to say the revision is controversial and not accepted by everyone. The Sydney Royal Botanic Gardens accepts it but the National herbarium in Canberra doesn't. Personally I think the revision has merit but that's by no means a popular view in the Society!

The red-flowering gum Corymbia ficifolia is one of the most widely recognised eucalypts.
Select the thumbnail image or highlighted name for a higher resolution image (43k).

The situation is now further confused by a more recent revision by Ian Brooker. This again moved Corymbia to sub-genus status (thus restoring the name "Eucalyptus" to species transferred by Hill and Johnson) and relegating the genus Angophora to sub genus status within Eucalyptus. The jury is still out on this revision!!

Basically you can make up your own mind as to whether or not you accept Corymbia. There is further info on the Eucalypt Page.

The page also has some useful links to the controversy.

Transpiration Beds for Sewage Disposal

Can you please let me know whether you have covered plants for transpiration beds in Gumnuts or elsewhere?

We are building on the edge of Wallaga Lake and the plumber has installed a large transpiration bed for the septic sysem, which is more than 100 metres from the lake (which is also beyond a rise in front of the system, so that our run-off heads west away from the lake for a further 200 metres before the land falls towards the lake).

What plants should we be growing on and around the transpiration bed?

Prue Neidorf
Wallaga Lake, New South Wales

There is a list of plants for land disposal areas in the New South Wales' on-site sewage disposal guidelines which can be viewed (or downloaded) from the NSW Department of Local Government's "Septic Safe" website.

Unfortunately the list is a little suspect. It is presumably covers New South Wales generally but, due to climate differences particularly east and west of the Great Dividing Range, any single list will inevitably contain unsuitable species for some areas.

Even allowing for this there are some curious suggestions (eg. Hibbertia stellaris, Scaevola ramosissima and Blandfordia sp) and many of the others will be hard to find as they aren't typical of what is available in nurseries.

Despite its limitations, the list is the best available at this stage.

Possible additional species that could be considered are low growing (up to 1 metre) bottlebrushes (Callistemon sp.), paperbarks (Melaleuca sp) and tea trees (Leptospermum sp).

Demise of River Red Gum

I have an interest in the medical properties of Eucalyptus. This interest comes from my love for plants and people.

While visiting Ameri-flora, I purchased a Murray River red gum (Eucalyptus camaldulensis). The tree has survived until this year when it succumbed to drought. The winters made it lose its secondary branches but the main terminals survived each year.

Many people would come by and comment on the beauty of the tree. I would like to replace it but want to know more about its habitat. Any specific information you may have will greatly be appreciated.

Dale Lafitte
USA

E.camaldulensis is the most widely distributed of all eucalypts - there is some info on its distribution and other features on the ASGAP web site.

Because of its wide range of habitats, it's ability to tolerate drought probably varies depending on the location where seed was collected. It certainly occurs in arid areas, usually along watercourses which may be dry for many years. It also occurs along rivers which have permanent water (eg. Murray River).

The name "Murray River Red Gum" is not used to any extent in Australia because the tree occurs in many other locations. We just call it the "River Red Gum".

Germinating Bunyas

I have a small arboretum of rare conifers in south west England and am particularly interested in the bunya pine (Araucaria bidwillii).

Bunya cone and seedsPhoto: Jan SkedSelect for larger image (37k)

I have been trying to propagate the bunya pine and have had little success. It has been suggested that the seed need to be fresh and, in the United Kingdom, you can only buy small quantities of seed from cold storage.

Do you know any outlet where I could buy a small quantity of the fresh seed from Australia. Or even better do you know of any outlets that will supply a small specimen (I have tried to search for this in Europe with little luck).

Chris Pullen
United Kingdom

I haven't any personal experience in propagating Bunya Pines so I don't know if fresh seed is necessary or not. However, seed of A.bidwillii is fairly readily available from many of the seed suppliers listed on our web site.

I don't have catalogues but some of the suppliers have email contact addresses so you should be able to contact them direct. AustraHort have it listed as available in March/April, so it sounds as if they supply fresh seed.

Plants for a Lorikeet

I very much enjoyed the society's web site. I am writing because I have a Red Lori and I'm always keen to try and find some flowers for it as I'm sure you know they are pollen and nectar eaters.

I know he enjoys eucalyptus and bottlebrush flowers, however flowering eucalyptus here tend to grow near busy, dusty highways, which according to bird literature, should not be used due to potential lead poisoning. I am therefore keen to try and grow my own and also extend the types of flowers I give him to be able to give him more, more often. At the moment I am wary of experimenting with flowers in case they may be poisonous (are mimosa or frangipani flowers poisonous?).

I was wondering if you could advise me on suitable species or if you knew where I may find such information.

Ideally I would like to grow them in pots (as I only have a large balcony), though I'm not sure how successful they would be at flowering. I am currently living in Beirut (Lebanon). The climate is sunny, hot and humid in the summer, and wet in winter though not cold (I doubt if it ever gets below 10 degrees C). I would also be interested in any species that could be grown in a garden in England as my bird spends time with my aunt there also.

Probably the best groups of plants for nectar feeding birds are Grevillea, Banksia, Anigizanthos and Eucalyptus.

Grevillea - there are hundreds available in Australia but I have no idea how readily available they would be to you. Any of the smaller varieties (say up to 1.5 metres should be able to be grown in large containers.

Banksia - these adapt well to pots. Even the larger species do well provided they aren't allowed to dry out.

Anigzanthos - Kangaroo Paws. These are smaller plants well suited to pots and the birds love them. Again, there are many available in Australia.

Eucalypts - Most are too large for containers but some of the smaller varieties would be worth trying, if you can get them. eg E.caesia, E.preissiana, E.youngii.

I'm not aware of mimosa (Acacia) or frangipani flowers being poisonous.

Info on Pomaderris

I was wondering if you could help me find any information about a type of pomaderris called Pomaderris pilifera?

A friend of mine recently bought me a small plant with this - and only this - as it's description. I have looked through my books and can't find any reference to it at all. I am trying to grow a garden to feed/house Australian native birds and animals, but I'd rather not have something that may spread like wildfire, or plant it in an inappropriate spot. Can you help me out at all?

Anything would be appreciated.

Alyssa Johnston
Victoria

The only thing that I could find out about this particular species is that it occurs in Tasmania so I asked John Wrigley to comment. John replied:

"Pomaderris pilifera is very unlikely to give you problems as an escape. P.pilifera occurs in southern NSW, Victoria and Tasmania often fringing water courses in dry sclerophyll forest. It is a shrub to about 3 metres high with lemon yellow flowers in panicles about 10 cm across. I don't know it in cultivation but I suggest from its habitat that it needs part shade and ample water."

Pomaderris are rarely seen in gardens - which is a pity because some species are very floriferous. This is Pomaderris humilis.
Select the thumbnail image or highlighted name for a higher resolution image (62k).

A Quiet Life

I am enquiring for help in creating a natural sound barrier adjacent to my property. I live about 100metres from a railway line, and have designed my house to reduce the noise from the trains which has worked quite effectively. I am wondering if I can further reduce the noise with a wind/noise barrier of native shrubs and trees.

Could you suggest types that are reasonably fast growing and that have dense foliage that would make them suitable for this application. I live on the east coast of Australia and we receive about 1250 mm of rain per annum. The soil is fairly shallow and over clay then into a conglomerate rock. I would appreciate you advice in this matter if it is not too much trouble. I live on an acreage so size is not a problem, in fact the bigger the better.

Geoff Lynch
Lake Macquarie, NSW

Interesting question - I've never really thought about using plants for noise control.

I would expect that plants recommended for visual screening would also work for noise screening with the added proviso that they should be dense foliaged. Selection will probably depend on what's available locally so I suggest you check out the list of native plant nurseries on our web site - there may be some in your area.

If space is no problem, a multi-layered effect would probably be best with larger trees in the back and a couple of rows of large, bushy shrubs in the foreground.

Pruning bottlebrushes

Three years ago I purchased four small trees They were my first natives and I was so excited that it wasn't until I got home that I realised that I had no name tags. With experience I realise that I paid too much... I have two pinks and one red and a purple tree.

This is the punch line...The purple tree has a lot of fresh growth...When do I prune the tree and do I prune it hard or light Or do I send it to tree heaven I do not know much about my natives The other three flower OK - what am I doing wrong with the purple tree.

Rae Pelly
Australia

Regrowth from a severely pruned CallistemonSelect for larger image (48k)

Callistemons can generally be pruned as hard as you like. I've pruned some back to almost ground level and had them recover well, as illustrated in the accompanying photo. Generally, though, it's best to prune after flowering, cutting off the spent flowers so that you get more branching and more flowers.